Hospitals do a barrage of sophisticated tests to determine brain death, said Dr. Cristobal Barrios, an associate professor and a trauma and critical care surgeon at the University of California, Irvine. He is not involved in Jahi's care and spoke about general hospital protocols.
The tests include touching a patient's cornea to elicit a blink, moving a breathing tube to stimulate a gag reflex, tickling the back of the throat to bring on a cough, and applying pressure or pain.
If the patient fails to respond to all of those tests, doctors remove the breathing tube for a few minutes. If there is any brain activity, the patient should begin breathing within a few minutes, he said.
In some cases, doctors will also draw a blood sample, add radioactive tags and re-inject it into the body to track where it flows. If the blood doesn't flow to the brain, Barrios said, there is no brain activity.
Generally, two teams of specialists must run the tests and determine independently that the patient is brain dead, he said. At UC Irvine, those evaluations must take place 12 hours apart if the patient is a child.
